Field of the Invention
The present invention relates to an internally pressurized component, in particular a high-pressure fuel accumulator for a common-rail fuel injection system of a motor vehicle, and to a method for producing an internally pressurized component of said type.
Description of the Background Art
A multiplicity of internally pressurized components, in particular for injection components of a motor vehicle, is known from the prior art. Such components may in this case be subjected to pressure loads of several hundred MPa, wherein, depending on the application, such pressure loads may also arise as pulsating pressure loads, which are particularly critical for the component.
To increase the compressive strength of such components, it is known in the prior art for such components to be subjected to a so-called autofrettage treatment, by way of which a considerable increase in strength of the components or of individual wall sections can be realized. Here, the component is subjected to an internal pressure which is higher than a subsequent operating pressure and higher than the yield strength of the material, specifically in such a way that regions on the inner wall of the component are plasticized, whereas regions on the outer wall remain elastic. As a result of the plasticized inner region, the elastically deformed outer region is prevented from fully deforming back into its initial position, such that the outer region remains expanded, and thus, in the inner region, an internal compressive stress is generated which counteracts the operating load. As a result, by way of an autofrettage treatment, the compressive strength of a component can be considerably increased. The known methods for autofrettage treatment are however increasingly reaching their limits, in particular with regard to the very high autofrettage pressures required for the autofrettage treatment and with regard to the material strength of the component itself.
It is also known in the prior art for separate inserts as so-called pressure oscillation dampers to be arranged in frictionally locking fashion within an internally pressurized component. Said separate inserts in this case comprise a reduced cross-sectional region, for example in the form of a bore running through the insert. Such separate inserts are however not suitable, or not adequately suitable, for increasing the compressive strength of a component, because the frictionally locking connection of separate insert and the component does not, or does not adequately, withstand the high pressure loading.